Continuous disc type dehydrating press

ABSTRACT

A continuous disc type dehydrating press of the type wherein a material is pressed between a pair of rotating pressing disc each rotatably mounted on a pivotable supporting shaft slightly inclined with respect to each other, said discs being disposed opposite to each other to define an annular groove of a V-shaped cross section between the confronting surfaces thereof. The press is provided with means for sealing the dehydrating zone against the outside air, which consists of an annular shoulder formed on a hub of each disc and defining a seal receiving surface, and a seal fixedly mounted on a seal mounting member with the peripheral edge of a central opening the seal in pressure engagement with the seal receiving surface, said seal mounting member being sealingly connected to each face of an annular casing defining the dehyration zone with the pressing discs accommodated therein.

United States Patent Yoritomi CONTINUOUS DISC TYPE DEHYDRATING PRESS [21] Appl. No.1 888,480

[58] Field ofSearch ..308/3.5,2l,238, 237 A; 277/30; 64/32 R, 32 F; 100/116, 158 C [56] References Cited UNITED STATES PATENTS 3,2l8,963 11/1965 Ginaven et al. ..l00/l58C 2,945,431 7/1960 Wehr ..lOO/l58C [451 Apr. 25, 1972 2,847,837 8/1958 Baker ..277/30 Primary Examiner-Leon G. Machlin Attorney-Karl W. Flocks [5 7] ABSTRACT A continuous disc type dehydrating press of the type wherein a material is pressed between a pair of rotating pressing disc each rotatably mounted on a pivotable supporting shaft slightly inclined with respect to each other, said discs being disposed opposite to each other to define an annular groove of a V-shaped cross section between the confronting surfaces thereof. The press is provided with means for sealing the dehydrating zone against the outside air, which consists of an annular shoulder formed on a hub of each disc and defining a seal receiving surface, and a seal fixedly mounted on a seal mounting member with the peripheral edge of a central opening the seal in pressure engagement with the seal receiving surface, said seal mounting member being sealingly connected to each face of an annular casing defining the dehyration zone with the pressing discs accommodated therein.

7 Claims, 7 Drawing Figures 1 CONTINUOUS DISC TYPE DEHYDRATING PRESS The present invention relates to sealing means of a continuous disc type dehydrating press.

The continuous disc type dehydrating press comprises a pair of rotary frusto-conically shaped pressing discs, each having a large number of liquid passage apertures bored therethrough and rotatably mounted on a shaft slightly inclined with respect to each other, said discs being disposed opposite to each other so as to form an annular spacing of a V-shaped cross section between the confronting conical surfaces of the respective pressing discs which is widest at a point and narrowest at a diametrically opposite point. An improved type of the aforesaid press wherein the angle of intersection of the shafts can optionally be changed, is known from the present inventors Japanese Patent No. 5369 9l (Japanese Patent Publication No. 19805/68, application No. 15347/64).

In the ,press disclosed in the above-mentioned Japanese patent, pressing discs are rotatably mounted on supporting shafts with the latter extending through hubs of the respective discs, and said shafts are pivotably connected witheach other at one ends, with the other ends being fixed at an optional point within grooves formed in a fixed frame respectively. Therefore, where a material to be processed, which is supplied intothe V-shaped annular spacing at the widest point is excessive in quantity with respect to the narrowest point of annular spacing of the pressing discs, there was the danger of the press being broken by the pressure of thematerial compressed and dehydrated at the narrowest point of the annular spacing. Under the circumstances, improvements have been proposed in the present inventor's US. Pat. application. (U.S. Ser. No. 835,937), now US. Pat. No. 3559567 issued Feb. 2, 197i, wherein shaft supporting means is provided on the fixed frame so as to support the outer end of each supporting shafts at an optional position and further the supporting force of the shaft supporting 'means is made adjustable. With such improvements, the supporting shaftslduring the operation are pivotable while having the outer ends thereof being supported by a substantially constant supporting force and thereby the maximum value of the compressive force, exerted on the material by the pressing discs, is automatically adjusted at a substantially constant value. Therefore, in the dehydration of material, the compressive force applied to the material is maintained substantially constant and the materialwill not be compressed by an excessively largeaforce," so that deformation of the material can be prevented.

However, in case the liquids to be extracted from-material are highly volatile and inflammable, such as methanol, it is necessary that the liquid extracting portion of the press is tightly sealed against the outside. This can be. attained by providing sealing means on the outer surface of the hub of the pressing disc. However, since the hub of the pressing disc rotates on the supporting shaft and also makes a pivotal movement along with the pressing disc, it is impossible to employ the ordinary mechanical seal or the like for this purpose (though the sealing of a material feed port, an expelled liquid discharge port and a residue discharge port can-be easily attained by a commonly practiced method).

The present invention is concerned with improvements by which the sealing of such portion as mentioned above can be attained completely which makes a pivotal movement simultaneously with a rotational movement, and the usefulness of the continuous disc type dehydrating press can further be enhanced. Namely, according to the present invention an annular shoulder is formed on the hub of the pressing disc to form an annular seal receiving surface defining a part of a spherical surface, while on the other hand an annular seal is sealingly fixed to the peripheral edge of a central opening of a seal mounting plate, with the inner peripheral edge thereof yieldably engaging said seal receiving surface, said seal mounting plate being air-tightly fitted oneach side of a fixed annular casing surrounding the outerperipheral edges of said pressing discs, whereby the rotatable and pivotable hub of each pressing disc can completely be sealed' by the engagement between the circular edge of the seal andthe seal receiving surface. I

The present invention will appear more clearly from the following detailed description when taken in conjunction with the accompanying drawings.

FIG. 1 is a side elevation of continuous disc type dehydrating press according to the present invention;

FIG. 2 is avertical cross section of the press;

FIG. 3 is a cross section taken onthe line Ill-ll! of FIG. 1;

FIG. 4 is an enlarged cross section of sealing means of the pressand 1 FIGS. 5, 6 and 7 are enlarged cross sections other forms of the sealing means of the press respectively.

Numeral l designates an annular casing having a certain breadth which is integral with a frame structure F. The. inner surface of the annular casing l defines a part of a-spherical surface. A circularplate member 2 concentrically disposed in the inner space of the annular casing l is fixed at theforward end of an arm plate 3 which is formed integrally with the annular casing l to extend radially inwardly from the inner surface of the casing. The outer peripheral surface of the circular plate member 2 defines a part of a spherical surface and has formed slantingly in the center thereof a rectangular throughhole 4 in which the inner ends of supporting shafts 5, 6 are supported by means of a pin 7 in such a manner as ,to be pivotable relative to each other. (The pin 7 is fixed to the circular plate member 2 at the opposite ends thereof.) Mounted rotatably on the respective supporting shafts 5, 6 are a pair of opposing pressing discs'8, 9 each having an integral hub 10 or 11 and being, formed with a large number of apertures 32 therethrough. Each of the pressing discs 8, 9 is formed in the front surface thereof with an annular recess in which thecircular plate member 2 is loosely received at one side. The outer peripheral surface of each disc 8 or 9 is placed close to the inner spherical surface of the annular casing LSprockets 12, 13 are firmly fixed on the hubs 10, ll of the respective discs 8, 9, through which a driving force is transmitted to the discs. The upper portions of side frames 14, i the frame structure F is formed therein with supporting grooves 16, 17 respectively for supporting the outer ends of the supporting shafts 5, 6. The outer end of each supporting shaft has an adjusting screw I8 threaded therethrough, by which the position of the supporting shaft is optionally adjusted. The adjusting screw 18 is in engagement with shaft supporting means, 19 at one end which is, for example, a resiliently supporting hydrauhe means consisting of a cylinder and a piston. A pressurized fluid supply conduit 20 is connected to the cylinder and a cock is provided at a mid portion ofsaid conduit 20. Between the cock and the cylinder is provided an accumulator. The sup porting shafts 5, 6 extend obliquely downwardly from the pin 7 toward the respective side frames, and the shaft end supporting grooves 16, 17 are formed in the same direction as that in which the respective supporting shafts 5, 6 extend. When the supporting shafts 5, 6 make a pivotal movement, the outer ends thereof oscillate along the lengths of the respective supporting grooves 16, 17 and thereby the widths of the V-shaped annular spacing defined by the pressing discs 8, 9 are slightly varied at the widest point and the narrowest point.

The annular casing I is provided with a material feeding hopper 21, a material discharging chute 22 and a liquid discharging port 23, each in an air-tight condition.

According to thepresent invention, the dehydrating zone between the pressing discs 8, 9 is sealed against the outside air. In this case, since the sprockets 12, 13 are mounted on the hubs 10, 11 of the respective discs 8, 9, the sealing means to be provided must be located inwardly of said sprockets l2, 13.

Furthermore, since the hubs 10, ll rotate and simultaneously oscillate incident to the pivotal movement of the respective supporting shafts 5, 6, the sealing means are required to be capable of complete sealing with respect to both rotation and pivotal movement of the supporting shafts 5, 6.

Now the invention will practically be described with reference to embodimentsthereof.

According to the invention, sealing means is provided on each side of the annular casing 1 in the same manner, so that only one of them which is provided on the left side of the an-. nular casing will be described herein. With reference to FIGS. 3 and 4, the hub of the disc 8 is formed with an annular shoulder 24 at a location inwardly of the sprocket 12, said shoulder having a surface defining a part of a spherical surface of which center coincides with the center of the pin. The surface of the shoulder provides a seal receiving surface. Since the surface of the shoulder forms a part of the aforesaid spherical surface said shoulder surface is always positioned on the aforesaid spherical surface even when the hub 10 rotates or simultaneously pivots around the pin 7.

A seal mounting member 25 is air-tightly fixed at the outer peripheral edge thereof to the peripheral edge of the circular opening of the annular casing 1 by means of bolts, through the intermediary of a packing. In the embodiment shown, the seal 25 is provided separately from the annular casing l but it may be provided integrally with the annular casing where more complete sealing is desired. The seal mounting member 25 extends radially inwardly toward the center thereof to define an opening 26 at the center. An annular rubber seal 27 is air tightly fixed at the outer peripheral edge to the inner edge of the opening 26 by means of bolts, and has the inner peripheral edge thereof in pressure contact with the spherical surface of the annular shoulder 24.

The embodiment described above is of the simplest structure, which is applicable to the case wherein the pressure created on volatilization of a liquid to be squeezed is very low, and in which sealing is maintained only by the elasticity of the rubber sea].

A material to be pressed is continuously fed through the airtight supply hopper 21. When the pressing discs 8, 9 are driven by a driving force transmitted thereto through the sprockets l2, 13 the material is pressed as the width of the V-shaped annular spacing between the pressing discs 8, 9 becomes narrower, and the hubs 10, 11 make a pivotal movement during this period, incident to the pivotal movement of the supporting shafts 5, 6. When the hubs 10, 11 make a pivotal movement while rotating, as described above, the point of engagement between the seal receiving surface of the annular shoulder 24 on each hub 10 or 11 and the inner circular edge of the seal 27 mounted on each seal mounting member 25 is constantly changed, but the condition of engagement is held constant, as said seal receiving surface is always positioned on the spherical surface whose center coincides with the center of the pin 7.

Where the sealing pressure is relatively larger, the only the elasticity of the rubber seal is insufficient to maintain a satisfactory sealing and thus the embodiment described above is not satisfactory sealing and thus the embodiment described above is not suitable to use. In such a case, the embodiment shown in FIG. 5 is advantageously employed. In this embodiment, as shown a resilient annular metallic plate 28 is applied to the outside surface of the rubber seal 27, so as to hold the rubber seal in pressure engagement with the seal receiving surface against relatively a larger pressure existing in the inner spacing ofthe annular casing 1.

Referring to FIG. 6, the embodiment thereshown is suitably employed in the case wherein the pressure in the annular casing 1 is varied. Namely, as shown, the rubber seal 27 is airtightly fixed at its outer peripheral edge to the seal mounting member 25 by means of a stepped annular fixture 28. The stepped annular fixture 28 is provided with a number of bolts 30 along the periphery of the central opening thereof, while the rubber seal 27 is provided with an annular plate 29 fixed to the outer side of the inner peripheral edge of the seal, and a coil spring 31 is mounted between each of said bolts 30 and said annular plate 29. It will, therefore, be understood that by screwing the bolts 30, the biasing forces of the respective coil springs 31 are adjusted and thereby the contact pressure between the rubber seal 27 and the seal receiving surface of the annular shoulder 24 is so suitably adjusted that the engagement therebetween may be maintained optimum. Such arrangement is also advantageous in that the rubber seal 27 can be advanced to the engaging position upon wear of the same.

Although in the embodiments described above, use is made of a rubber seal as the sealing element, a seal of a synthetic rubber or a synthetic resin may be used in lieu of the rubber seal where the seal element to be used is required to be resistant to corrosion, due to the characteristic of the volatile liquid to be extracted. However, an increasing frequency of use of the apparatus or an increasing number of revolution of the pressing discs accelerates wear of the contacting portion of the seal, making it impossible to maintain the satisfactory sealing throughout the operation. In such a case, use of the embodiment shown in FIG. 7 is preferable. In this embodiment, use is made as the seal a cylindrical seal 31 which has one end securely fitted in an annular groove formed in the inside surface of the inner peripheral edge portion of the seal mounting member 25 and the other end in pressure engagement with the spherical seal receiving surface of the annular shoulder 24. According to this embodiment, the circular edge of the inner end of the cylindrical seal stretches out, as the engaging surface thereof is worn off, under the compressive force stored therein and thereby the pressure engagement between said cylindrical seal and the seal receiving surface of the annular shoulder 24 can be maintained even after the engageing surface of said cylindrical seal has been worn off to a considerable extent.

As will be understood from the practical embodiments of the invention described and illustrated herein, according to the invention the engagement between the circular inner edge of the seal and the seal receiving surface of the annular shoulder formed on each hub is maintained always under the same sealing condition, in spite of the rotation and pivotal movement of the hub, so that a satisfactory sealing can be maintained under any condition throughout the operation, insuring a safe operation.

What I claim is:

l. A continuous dis'c type press comprising a substantially annular casing supported by a stationary frame, a pair of supporting shafts pivotally connected at their inner ends within said casing and extending outwardly through openings in said casing, supporting grooves on said stationary frame for supporting the outer ends of said shafts, means carried by each of said grooves for adjusting the force applied to the outer end of each of said supporting shafts thereby to effect pivotal movement of said shafts, a pair of opposed pressing discs, each disc having a hub by which it is journaled for rotation about the inner end of one of said supporting shafts inside said casing, each of said hubs extending outwardly through said opening to terminate outside said casing for pivotal movement with said one of said shafts in response to the adjusting force, a disc-like annular seal member fixedly mounted on said casing concentrically about each of said openings and encircling the hub extending therethrough, each of said seal members being secured to the casing at its outer periphery and being directed radially inwardly into continuous yieldable pressure engagement with the surface of said hub to close the space between said casing and said hub.

2. The press of claim 1 wherein each of said hubs has an outwardly facing shoulder with a seal receiving surface formed as a part of a sphere.

3. The press of claim 2 wherein said seal member is mounted on the outside of said casing.

4. The press of claim 3, including a resilient means fixed to said casing in contact with the outside surface of said seal member for continuously urging it against said seal receiving surface.

5. The press of claim 4 wherein said resilient means comprises an annular resilient ring-shaped member overlying the outside surface of said seal member for continuously urging the seal against said seal receiving surface.

6. The press of claim 4 wherein the resilient means comprises a coil spring for continuously urging said seal member against said seal receiving surface.

7. The press of claim 4 wherein said seal member comprises a substantially annular elastomeric member. 

1. A continuous disc type press comprising a substantially annular casing supported by a stationary frame, a pair of supporting shafts pivotally connected at their inner ends within said casing and extending outwardly through openings in said casing, supporting grooves on said stationary frame for supporting the outer ends of said shafts, means carried by each of said grooves for adjusting the force applied to the outer end of each of said supporting shafts thereby to effect pivotal movement of said shafts, a pair of opposed pressing discs, each disc having a hub by which it is journaled for rotation about the inner end of one of said supporting shafts inside said casing, each of said hubs extending outwardly through said opening to terminate outside said casing for pivotal movement with said one of said shafts in response to the adjusting force, a disc-like annular seal member fixedly mounted on said casing concentrically about each of said openings and encircling the hub extending therethrough, each of said seal members being secured to the casing at its outer periphery and being directed radially inwardly into continuous yieldable pressure engagement with the surface of said hub to close the space between said casing and said hub.
 2. The press of claim 1 wherein each of said hubs has an outwardly facing shoulder with a seal receiving surface formed as a part of a sphere.
 3. The press of claim 2 wherein said seal member is mounted on the outside of said casing.
 4. The press of claim 3, including a resilient means fixed to said casing in contact with the outside surface of said seal member for continuously urging it against said seal receiving surface.
 5. The press of claim 4 wherein said resilient means comprises an annular resilient ring-shaped member overlying the outside surface of said seal member for continuously urging the seal against said seal receiving surface.
 6. The press of claim 4 wherein the resilient means comprises a coil spring for continuously urging said seal member against said seal receiving surface.
 7. The press of claim 4 wherein said seal member comprises a substantially annular elastomeric member. 